Oil still



C. E. LUCKE May 9, 1933.

OIL STILL Filed March 28, 1928 3 Sheets-Sheet 1 5 MVENTOR ATTORNEY y1933- c. E. LUCKE 1,908,375

OIL STILL Filed March 28, 1928 3 Sheets-Sheet 2 lNVE TOR ATTORNEUPatented May 9, 1933 UNITED STATES PATENT OFFICE CHARLES E. LUCKE, OFNEW YORK, N. Y., ASSIGNOR TO THE IBAIBCOCK &, WILGOX COMPANY, OFBAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY OIL STILL Applicationfiled March 28, 1928; Serial No. 265,247.

This invention relates to an oil still that is located above a furnaceand is shielded from the radiant heat of the furnace by means of watertubes that may be connected,

for example, to the circulation system of a Water tube boiler. Theinvention will be understood from the description in connec tion withthe accompanying drawings in which Fig. 1 is a vertical section throughan 19 illustrative embodiment of the invention and Fig. 2 is a similarsection showing a modification. Fig. 3 is a sectional view on line 3-3of Fig. 1.

In the drawings, reference character 5 indicates a furnace that isprovided with the water space of which is connected to downtake headers8 by means of tubes 9. Uptake headers 10 are connected to the steam andWater drum 7 by means of side wall tubes 11 and roof tubes 11. Theheaders 8 and 10 are connected by rows of inclined or drop leg tubes 12,constituting a bank of tubes. A pipe 13 leads from the steam space ofthe steam and Water drum 7 to a superheater 14 located above the bank oftubes 12. The number and disposition of the tubes 12 is such that verylittle, if any, radiant heat can pass between the same and becomeabsorbed by the oil tubes located above the bank 12. The number of tubesis preferably limited to the smallest number of tubes that willsufiiciently screen the oil tubes from the radiant heat of the furnaceso that the furnace gases will not be appreciably cooled before theyreach the tubes above the screen.

The space above the tubes 12 is divided into conduits or gas passages15, 16 and 17 by means of baffles 18 and 19, so that the successive gaspassages decrease in cross sectional area. The upper end of the bafile18 terminates short of the upper end of the passages 15 and 16, and itslower end is connected by meansof a baffle 18 lying along the upper rowof the bank of tubes 12 and extending-to the headers 8. The baffle 19extends downwardly from the roof tubes 11 and terminates short of thebaflle 18. A conduit leads from the outlet 20 for the waste gases'to anair heater 21, to which a suction fan 22 is connected. The outlet. ofthe suction fan leads to the stack 23. A fresh air fan 24 forces airthrough the air heater, thence through the conduit 25 into'passagesoutside of the conduits 15, 16 and 17, from which it passes to the spacein front of the furnace 5, and thence into the furnace for combustionpurposes. A branch 28 may lead from the fan 24 to spaces along theoutside of the furnace 5, and thence into the space 27 and thence intothe furnace.

An oil inlet pipe 30 leads to the upper portion of the conduit 17 and isconnected to the end of a straight tube 31 that extends horizontallyacross the passage 17.

The tube 31 is connected by a return bend connection 32 to a similarparallel tube that is connected in series with the next tube, and

so on, through the group of tubes that are located in the passage 17.The last one of the tubes 31 is connected to the end of a similar tubein the gas passage 16. The tubes in the gas pasage 16 are connected andlocated similar to the tubes 31 so that the oil passes in series throughthese tubes into similar tubes 34 in the upper portion of the gaspassage 15. The outlet end of. the tube group 34 is connected to aheader 35 which is common to the upper row of tubes of the group 37. Thetubes in the upperrow have their ends connected by return bends to alower row and. so on, through a plurality of tubes the last row of whichhave their ends connected to the header 38 on the outside of the walland an outlet 39 leadsaway from the outlet header 38.

The pipe 13 from the steam space of the steam and water drum 7 leads tothe superheater' inlet header 40 that is connected by the superheatertubes 14 to the outlet header 41 from which a pipe 42 leads to theheader 35 so that the superheated steam is mixed with the oilvapors asthey enter the tubes 37.

The operation is as follows: Hot products of combustion from the furnace5 pass over water-tubes 12, which act as a radiant .heat screen, andthence overthe oil tubes in the gas passages 15, 16 and 17 The wasteproducts of combustion then pass through the air heater 21 where airthat may be utilized for combustion purposes in the furnace is heated.

Water from the steam and water drum 7 passes downwardly through thetubes 20 into the headers 8 and as it flows upwardly through the tubes12, steam is generated and heated and finally pass out through theoutlet39. The size of oil tubes in the passages 15, 16 and 17 is suchand the rate of feed of the oil therethrough is of sufficient velocityto cause turbulent flow of the oil through the tubes, so that danger ofoverheating films of oil on the inside surfaces of the tubes iseliminated. Oil flowing in turbulent condition is well mixed in thetubes so that when the oil and vapors pass into the tubes 37 they are atuniform temperature throughout and portions thereof are not cracked inan objectionable manner because of local overheating or excess heat'inspots.

The superheater for the steam may be entirely dispensed with and nosteam mixed with the oil while the oil is being distilled In this casethe steam generated in the steam boiler may be used for other purposes.When the steam from the steam boiler portion of the device is mixed withthe oil vapors, less steam or no steam is required from an outsidesource for this purpose.

In the modification shownin Fig. 2, the same parts that have beendescribed above are referred to by the same reference characters and itis not thought necessary to repeat the description. In thismodification, the superheater 14 is made up of U-tubes connected to theinlet headers 40' and 41, the legs of. these U-tubes being parallel tothe inclined tubes 12. The steam generating portion of this arrangementmay generate steam that is used for any desired purpose. Or, thesuperheated steam from the superheater 1 1 may be caused to mix with theoil vapors as above described in connection with Fig. 1 if desired. Inthis modification, the tubes 34 through which the oil passes are shownas occupying substantially the entire space of the gas conduit 15 and nomixture of the steam from the superheater with the oil vapors isindicated. The oil vapors after being heated in the tubes pass outthrough the outlet 38. The steam sup'erheajter may be entirely omittedand the device will operate whether steam ismixed with the oil vapornear the end of the distilla tion operation or not.

In both illustrations of the invention the gas passes above the radiantheat screen decrease in cross sectional area so that the velocity of thegases is kept up even while the gases are being cooled by passing overthe oil tubes. Decreasing the gas path adds to the efficiency anddecreases the amount of surface that would otherwise be required. Verylittle of the heat of the gases from the furnace is abstracted bycontact with the tubes 12 so that a sufiicient amount of heat is left inthe gases to distill and crack the oil that passes through the tubes inthe gas passages 15, 16 and 17.

With this invention it is not necessary to temper or cool the furnacegases before allow ing them to contact with the oil tubes. Very highefficiency can also be obtained because hot aircan be introduced intothe furnace for combustion purposes and it is not necessary to use alarge amount of excess air. Products of combustion at considerably hightemperatures can be permitted to escape and the air heater used torecover heat therefrom.

I claim:

1. In an oil still, a combustion chamber, a gas passage of graduallydecreasing area leading from said combustion chamber, straight oil tubesconnected in series and located in said gas passage, and radiantlyheated tubes comprising. drop leg water tubes of a water tube boilerlocated between said straight tubes and said combustion chamber, thenumber and disposition of said radiantly heated tubes being such thatthe temperature of the hot products of combustion passing across them isnot appreciably lowered.

2. In an oil still, a combustion chamber, a gas passage of graduallydecreasing area leading from said combustion chamber, straight oil tubesconnected in series and located in said gas passage, and radiantlyheated tubes comprising drop leg water tubes of a water tube boilerlocated between said straight tubes and said combustion chamber, andmeans to cause steam from said boiler to commingle with oil vapors inthe tubes located in from entrance to outlet, a thermosiphonic"circulation water tube boiler having its tubes disposed in radiant heatrelation with respect to said combustion chamber and shielding the gaspassage, and oil heating tubes disposed in said gas passage andproviding a continuous flow from the cooler portion there of to thehotter portion, and .a superheater' in the hotter portion receivingsteam generated in the boiler and delivering superheated steam to theoil passage at a location near the hotter end thereof. 2

4. In combination, a furnace including a combustion chamber and awinding gas passage therefor of gradually decreasing area from entranceto outlet, a thermosiphonic circulation water tube boiler having itstubes disposed in radiant heat relation with respect to said combustionchamber and shielding the gas passage, and oil heating tubes disposed insaid gas passage and extending strai ht across same and providing acontinuous ow from the cooler portion thereof to the hotter portion, anda superheater in the hotter portion receiving steam generated in theboiler and delivering superheated steam to the oil passage at a locationnear the hotter end thereof.

5. In combination, a furnace including a combustion chamber and aWinding gas passage therefor of gradually decreasing area from entranceto outlet, a thermosiphonic circulation water tube boiler having itstubes disposed in radiant heat relation with respect to said combustionchamber and shielding the gas passage, and oil heating tubes disposed insaid gas passage and extending straight across at right angles to theboiler tubes and providing a continuous flow from the cooler portionthereof to the hotter portion, and a superheater in the hotter portionreceiving steam generated in the boiler and delivering superheated steamto the oil passage at a location near the hotter end thereof.

CHARLES E. LUCKE.

